# Python: Fix the Invalid Literal for int() Error

> Catch a ValueError before calling int() on user input, or convert the string through float() first, to handle empty strings and decimal values safely

**URL:** https://sentry.io/answers/invalid-literal-for-int-error-in-python/

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## The Problem

My Python script fails with this error:

```
ValueError: invalid literal for int() with base 10: ''.
```

What causes this and how do I fix it?

## The Solution

This error message arises from a failure to convert an empty string (`''`) to an integer. This might arise in the following script if the user presses Enter without providing any input:

```python
user_input = input("Enter a whole number: ")

print(f"Your number is 1 smaller than {1 + int(user_input)}")
```

To prevent this error, we should check that our string is not empty before passing it to `int()` for conversion:

```python
user_input = input("Enter a whole number: ")

try:
    print(f"Your number is 1 smaller than {1 + int(user_input)}")
except ValueError:
    print("Please provide a valid number.")
```

A similar error might arise if the user provides a number with decimal places, such as `1.0`. We can avoid this error by converting the string to a float before converting it to an integer:

```python
user_input = input("Enter a whole number (non-whole numbers will be rounded down): ")

try:
    print(f"Your number is 1 smaller than {1 + int(float(user_input))}")
except ValueError:
    print("Please provide a valid number.")
```

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*Source: [sentry.io/answers/invalid-literal-for-int-error-in-python/](https://sentry.io/answers/invalid-literal-for-int-error-in-python/)*